Manufacture of molded binder-reinforced fiber articles of pliant character



Nov. 15, 1938. M. o. SCHUR 2,136,325

" MANUFACTURE OF MOLDED 'BINDER REINFORCED FIBER ARTICLES OF PLIANTCHARACTER Filed Sept. 4, 1935 2 Sheets-Sheet 1 I Nov. 15, 1938. M. o.SCHUR 2 MANUFACTURE OF MOLDED BINDER-REINFORCED FIBER ARTICLE E. PLIANTCHARACTER Filed pt. 4, 1955 2 Sheets-Sheet 2 I|IIITIIT| Patented Nov.15, 1938 MANUFACTURE OF MOLDED, BINDER-REIN- FORCED FIBER ARTICLES FPLIANT CHARACTER Milton 0. Schur, Berlin,

Company. Berlin, N.

Maine N.. H., assignor to Brown R, a corporation oi ApplicationSeptember 4, 1935, Serial No. 39,197

3 Claims.

This invention relatesto the manufacture of molded, binder-reinforced,fiber articles of a pliant character, for instance, articles of apliancy comparable to that of suede or of the felt in a true .felt hat.It deals more especially with articles of the sort whose molded fibrousbase is an interfelted, Waterlaid one in the sense that it is depositedby flowing an aqueous fiber suspension onto a foraminous or wire moldthrough which the free water of the suspension drains or is sucked whilethe fibers are being matted or laid down in inter-felted relationship asa layerconforming to the configuration of the mold.

In accordance with the present invention, various kinds of molded,binder-reinforced, fiber articles of a pliant character, for instance,hat shapes, are formed by depositing fibers of the appropriate characterfrom aqueous suspension onto foraminous molds, the aqueous suspensioncarrying additionally, if desired, binder of suitable character so thatthe binder-reinforced articles maybe formed in a single operation; or,

shape and preferably both-its surfaces if desired, the molded articlesmay be formed substantially without binder as sufliciently porous andabsorptive structures to undergo readily a subsequent impregnatingoperation with suitable binder, the articles preferably being compactedand dried prior to such impregnation. While not limited thereto, theprinciples of the present invention are applicable to especial advantagein the fabrication of seamless hats whose appearance, feel, pliancy,toughness and other qualities are imitative of those of genuine felthats. In such case, after the binder-reinforced hat shape has beenproduced as hereinbefore in-' dicated, at least the external surface ofthe hat are 1111- ished with fiber 11001: to simulate in appearance andfeel the surface of a genuine felt hat.

With the foregoing and other features and objects in view, I shall nowdescribe my'invention as applied to hat-making with particular referenceto the accompanying drawings, wherein Figure 1 is a section through oneform of apparatus that may be employed for molding a hat shape, theapparatus including adjuncts for compacting and, if desired, drying thewet hat shape Figure 21s a section through somewhat modified moldingapparatus during themolding oper-' ation, with which apparatus adifferent type of instrumentality for compacting the wet hat shape isdesigned. to be used. I

Figure 3 is a similar view of the apparatus of Figure 2 after themolding operation and with the compacting instrumentality in place.

Figure 4 is a similar view of the same apparatus while compacting of thelayer constituting the hat shape is being eiiected.

Figure 5 is a side view of the molded hat shape. Before dealing with theparticular fiber furnish, binders, and other materials employed'infabricating the hats of the present invention, it is perhaps well todescribe the particular molding apparatus shown in the accompanyingdrawings, which apparatus, it is to be understood, is subject toconsiderable variation. The apparatus of Figure 1 comprises acylindrical vat l0 into which an aqueous fiber suspension of theappropriate consistency, namely, of a fiber content usually notexceeding about 2%, is delivered from a suitable source of supply (notshown) by a valved pipe I I. In order to realize uniform interfelting ofthe fibers as they are being deposited from aqueous suspensicmit ispreferable to deliver very dilute fiber suspensions to the apparatus,for instance, suspensions of a fiber content of to or even lower. Theapparatus as depicted in Figure 1 comprises only a single wire mold l2,but it is obvious that multiple-mold apparatus may be employed. The moldillustrated, which assumes the form of an inverted hat shape, may beconstructed of wire cloth of a mesh and quality similar to that servingas the endless wire of a Fourdrinier papermaking machine or as theperiphery of the cylinder mold of a so-called cylinder papermakingmachine. Its marginal portion l3 may be fixed, as by welding, to theout-turned flanged upper end portion ll of a cylindrical supportingframe l5 movable vertically out of the vet along with the mold carriedthereby while guided in such movement by a cylindrical outer shell ISwith which it makes sliding contact. The lower end of the shell I may befixed to the bottom ll of the vat and its upper end may serve as up themold so as to deposit a substantially uniform layer of fibers It on themol d as-the water of the suspension is draining through the mold intothe compartment 2|! defined by the shell [6. A valved pipe 2| forwithdrawing the white water from the compartment 20 is kept open duringthe molding operatiomwhich operation is preferably initiated with asupply of white water in the compartment 20 up to the very top of themold, namely, to the level of its marginal portion [3, so as to avoid a"water-wing eifect, that is, an immediate sealing of the openings of themold by the water of the pulp suspension that prevents osited on themold is compacted the valve 22 in the pipe 2| is preferably a twoway onedesigned to permit downward flow of white water from the compartmentthrough its branch 23 during a molding operation and upward fiow ofwhite water through its branch 24 into the compartment before beginninga molding operation. Aqueous suspension of fiber in volume predeterminedto deposit a layer of fibers IQ of the desired thickness on the mold isprogressively delivered into the apparatus and the valved pipe-Ii thenclosed.

Inasmuch as the hat shape l9 as deposited on the mold is too wet andpulpy to be removed from the mold or handled without damage, provisionis made to compact and dewater it to a self-sustaining condition. Tothis end, the molding apparatus of Figure 1 includes means for raisingthe mold-supporting frame l5 while guided by the shell I6 out of the vatso as to bring the wet hat shape carried by the mold into pressingcontact with a compacting instrumentality 25 of a configuration matingwith that of the mold, as illustrated in dotted outline. Thus, the lowerwalls of the mold-supporting frame l5 may be bridged by a transverse bar26 fixed in turn to the upper end portion of a plunger or reciprocatablerod 21 passing through a suitable stufllng box 26 into the compartment26. Movement of the plunger may be effected by suitable means (notshown) to raise the wet hat shape carried by the mold I9 into pressingcontact with the compacting instrumentality 25 and then to lower themold to its molding position in the vat. If desired, the instrumentality25, which may! be constructed of suitable metal, such as steel, and besmoothly finished .on its exterior, may have a hollow interior 29 intowhich steam or other suitable heating medium may be introduced by a pipe30 so that upon bringing the wet hat shape into the desired pressingcontact therewith, not only may the free water be squeezed from theshape but the shape may be partially or completely dried. Once the hatshape has been compacted and dewatered to a self-sustaining condition,so that it may be removed from the mold and handled without injury, apartial downward movement of the plunger 21 may be effected to permitthe hat shape to be removed for further treatment, whereupon theremaining downward travel of the plunger may be completed.

The hat-molding apparatus shown in Figure 2 is essentially similar tothat of Figure 1 excepting that no provision is made for raising themoldsupport to bring the hat shape carried by the mold .into pressingcontact with a compacting instrumentality. On the contrary, the mold 40appearing in the apparatus shown in Figure 2 is removably supported atits marginal portion 4| on an annular ledge 42- projecting inwardly fromthe upper portion of a cylindrical wall 43 .upstanding from and fixed tothe bottom of the vat and defining a compartment 44 into which whitewater drains from the mold during the delivery of aqueous fibersuspension thereon. Leading from the compartment 44 is a two-way valvedpipe 2|. having the same connections and the same functions as thesimilarly numbered pipe and connections of the apparatus of Figure 1.

The essential distinguishing feature between the apparatus of Figure 2and that of Figure 1 is the means by which the wet hat shape lsdeanddewatered to'self-sustaining condition. Thus, as shown in Figure 3,after a wet hat shape has been deposited as previously described on themold 46, a membrane 45 of rubber or equivalent stretchable andgas-impermeable material cemented or other wise fixed to a rigidmarginal retaining ring 46 is placed over the mold with the marginalportion of the membrane or the ring 46 making sealing contact with themarginal portion 4 of the mold. The membrane or diaphragm 45, whichnormally extends horizontally over the top of the mold so as to closeoff the top completely, is thus in a position to be sucked or stretcheddownwardly against the hat shape into the mold-conforming configurationshown in Figure 4, and, in so being stretched, to squeeze the free waterfrom the wet hat shape and thus to compactv it to a self-sustainingcondition. The membrane may be placed under the appropriate suction bycreating suction in the compartment 44 by opening a valved suction pipe41 leading from such compartment to a vacuum chamber or pump (notshown). The valve 48 in the pipe 41 is preferably a two-way one, one wayopening to a branch 49 communicating with the vacuum chamber or pump andthe other to a branch 50 communicating with the atmosphere. After thedesired compacting and dewatering of the hat shape has beenaccomplished, the suction branch 49 is closed and the atmosphericpressure branch 50 is opened to permit restoration of the compartment 44to atmospheric pressure. In order to permit air to pass in between themembrane and the hat shape so as to break the suction that tends topersist therebetween and thus cause the membrane to peel away graduallyfrom the hat shape and resume its normal unstretched position shown inFigure 3, the membrane is preferably provided, as at its center, with avalved, open-ended nipple 5| projecting upwardly there- -fr0m, themembrane being cemented or otherwise sealed to a thin flange element 52constituting the lower end of the nipple. The nipple is closed whilesuction is being applied to the membrane and is opened sufficiently whenair is subsequently introduced into the compartment 44 to permit it topeel away gradually from the compacted and' dewatered hat shape and thusto resume its normal unstretched position. The membrane and its rigidretaining ring 46 may then be removed from the mold, the mold and thehat shape carried thereby raised from its support, and the hat shapedried preferably while stillv carried by the mold, as in a hot airchamber.

Various binders may be used to impart the desired toughness andleather-like qualities to the fibrous body of the hat, for instance,such binders as rubber, glue, viscose, etc. These binders may be addedto the aqueous suspension of fibers delivered to the hat-moldingapparatus, in which case the white water system of the apparatus shouldpreferably be maintained reasonably closed so as to utilize the bindercarried away by the white water in preparing fresh or new fibersuspensions. In the case of rubber, the rubber may be added to theaqueous fiber suspension as at 4 to 6% fiber content in the form ofrubber latex or artificial aqueous rubber dispersions and the rubberprecipitated or coagulated on the fibers beforebeing diluted with waterfor delivery to the molding apparatus; or a dilute aqueous suspension offlocculated or precipitated rubber may be separately prepared fromrubber latex or other aqueous rubber dispersion and admixed with thedilute aqueous fiber suspension immediately before its delivery to themolding apparatus. It may, however, be prefer able to impregnate thepremolded hat shape in partially or completely dried condition. Thus,the premolded hat shape may be sprayed on either or both faces withrubber latex or other suitable binder to effect a substantialimpregnation of itsbody, or, if desired, a substantially completeimpregnation thereof.

Irrespective of whether the hat shape is molded in the presence ofbinder or whether binder is subsequently infused thereinto, it isthen-preferably surfaced with fiber flock so as to simulate true felt orsuede in its appearance and feel. If the hat is-molded in the presenceof binder and is then dried, it is necessary to apply suitable binder,such as rubber I latex, glue, nitrocellulose cement, etc., as byspraying, on the surface of the hat and then to shower fiber flock onthe sticky hat surface as the hat is supported on a suitable form orblock, with rotary or other appropriate movement of the form, ifdesired, to ensure substantially uniform flocking of the hat surfacewith fiber. At least the outer surface of the hat is preferably thusfinished with fiber flock; and it is usually desirable to turn the, hatinside out on the supporting form after its outer surface has beenfinished and to finish the nowouter surface in the same way as thepreviously outer surface. In those instances when the molded hat shapeundergoes an after-impregna tion with rubber latex or other suitablebinder, as by spraying the binder on the shape while supported by a formor block, sufficient binder may be applied not only to effectimpregnation of the body of the shape to the desired degree but todevelop an adhesive coating on its surface which is showered with fiberfiock and then permitted to dry or set. Thereupon, if desired, theinside surface of the hat may'be treated with binder and also flocked,as hereinbefore described. Of course, fiber flock of any'suitable coloror sheen may be employed; and, if desired, flock of one or more colorsmay be distributed locally on the hat surface to produce highlyornamental eifects, the binder for the flock and/or the flock beingapplied, for instance, through suitable stencils in producing sucheffects.

In some cases it is advantageous to form the hat into a shape which onlyroughly conforms to the final desired pattern, then re-wetting andstretching over a mold or form against which the material will shrinkduring re-drying. The hat may then be flocked in the usual way.According to this procedure the number of relatively expensiveforaminous molds necessary for the deposition of the pulp mayberconsiderably reduced,

and changes in final hat shapes may be efiected through the stretchingprocess.

The flocked or finished hat may be given a final blocking or shaping asis customary in hat manufacture; and it may be provided with the usualaccessory hat elements, such as a lining, sweat band, etc., and theusual hat ornaments, such as an outer band or ribbon, buttons, feathers,buckles, etc.

- An important factor in the realization of hats possessed of the.desired body, feel, pliancy, and other qualities is the character of thefiber furnish employed in molding the hat shape. Thus, unless thefurnish is of the proper kind and is properly conditioned for thehat-molding operation, the resulting hat shape may be comparativelyrigid or boardy, as is true of the usual molded pulp articles. Inaccordance withthe present invention, I supply to the 'moldin'gapparatusaqueous suspensions of cellulosefibers preferably in substantiallyunhydrated condition, for instance, suspensions of cellulose fibers of adimcultly hydratable character in such condition,

typical of which fibers are wood pulps refined to high alpha cellulosecontent,-say,"an alpha oel- "lulose content of about 92% to 98%, virgincotton,

mercerized wood pulps or cotton, and the like. In suspending such fibersin water to form the dilute suspension delivered to the moldingapparatus, care should be takento avoid substantial beating or otherintensive mechanical action such as is accompanied by a hydration orgelatinization of the fibers and consequent .stiifness or I boardinessin articles molded from the fiber susgreater degree than is otherwisepermissible, asv

wool and/or hair are unhydratable and lend to the molded hat shape thedesired pliancy and other qualities.

Indeed, when, say, 5% to 65% of wool and/or hair, based on the dryweight of the entire fibrous furnish constitutes, along with cellulosefiber, the fibrous furnish, it may be desirable to effect some degree ofhydration or gelatinization of the cellulosic fibrous portion of thefurnish in order to effect a binding or cementing together of the fibersof the hat base by the cellulose hydrate or gelatinized cellulose. Partof the fibrous furnish may be long-fibered pulps, such as chemicallypulped manila, sisal, ramie, etc., 5% to 50%, based on dry weight of thefurnish, of such long-fibered pulp improving notably the results securedfrom furnishes containing a substantial proportion of mercerizedcellulose fiber and/or wool.

Various proportions of binder may serve as the reinforcing impregnant inthe hat shape. Thus, the hat-shape may contain from about 5 to 100% ofrubber, or from about 8 to 40% of glue, or from about to 5% of celluloseregenerated from viscose, based on the dry weight of fiber in the hatshape. In the case of all of these binders and especially in the case ofglue and viscose, it is desirable to introduce a suitable softening orplasticizing agent into the hat shape in order to neutralize or offsetsuch undesirable stifiening action of the shape as may come from thebinder.

, Thus, hat shapes impregnated with dry rubber latex solids may toadvantage contain about 5 to 25%of glycerine, based on latex solids;those impregnated with glue, about '75 to 200% of glycerin-e, based onglue solids; and those impregnated with about V to 5% celluloseregenerated from viscose, about 5 to 30% of glycerine, based on the dryweight of fiber. Other softening )agents, such as ethylene glycol orother homologues of glycerine, glucose or, other invert sugars,Nulmoline, and the like might be employed in lieu of glycerine. Theglycerine or other softening agent may be introduced directly into suchimpregnants as rubber latex, glue solution, and'visdose, with which theymay be applied to the binder-impregnated hat shape either generally orlocally, as in the form of aqueous solutions. So, too, such stiffeningagents as waterglass, starch paste, etc., maybe added to'the hat shapealong with the binder. In some instances, binders such as rubber latexare "compatible; or they I and glue, rubber latex and viscose, andrubber latex, glue and viscose may be admixed to develop the properdegree of stifiness in the hat. In this connection, it might be notedthat the addition of glue and/or viscose to a rubber latex binder hasthe effect of increasing the stiffness of the hat shape impregnated withthe binder. As in the case of the softening agent, the stifiening agentmaybe infused into the binderirnpregnated hat shape, as in the form ofan aqueous solution; and such infusion may be had generally or locally,for instance, only at'the brim portion of the hat, whereat greaterstiffness is generally desired than at the crown portion.

While the thickness of the hat body or structure prior to surfacing itwith fiber flock is sub- Ject to variation, it is generallythe case thatthe thickness desired ranges from about 20 to 60 mils, as at suchthickness it can be finished with fiber flock to produce a final hatstructure or body whose'thickness is comparable to that of suede or feltin a-true felt hat.

I claim:-

1. A method of making a seamless, molded, binder-reinforced, waterlaidfiber article which comprises depositing fiber and an elastic binder'from aqueous suspension into approximate article shape on a porous mold,compacting the article to remove free water therefrom and dewatering itto self-sustaining condition on said mold,

so removing the dried article from said mold, re-

wetting and stretching the article in rewetted condition to its finalshape on another mold, and redrying the article on said other mold,thereby causing it to shrink against said other mold.

2. A method of making a seamless, molded, rubber-reinforced, waterlaidfiber article which comprises depositing fiber and fiocculated rubberfrom aqueous suspension into approximate article shape on a porous mold,compacting the article to remove free water therefrom and dewatering itto self-sustaining condition on said mold, removing the dried articlefrom said mold, rewetting and stretching the article in rewettedcondition -t.o-its final shape on another mold, and redrying the articleon said other .mold, thereby causing it toshrink against said othermold.

3; A method of making a seamless, molded, waterlaid fiber article whichcomprises depositing 'fiber from aqueous suspension into approximatearticle shape on a porous mold, compacting the article to remove freewater therefrom and dewatering it to-self-sustaining condition on saidmold, removing the article from said mold,

stretching the article, in whose body an elastic binder is incorporatedas an impregnant, in the presence of moisture to its final shape onanother mold, and drying the article on said other mold,

thereby causing it to shrink against said other mold.

MILTON O. SCHUR.

